xviii 



131a. Leaves with glands on the petiole or at the base of the leaf- 

 blade 132. 



I31b. Leaves with small dark glands on the upper side of the mid- 

 vein 42a, in ROSACEAE, p. 54. 



131c. Leaves without glands 133. 



132a. Willows; with usually slender leaves, frequently con- 

 spicuous broad stipules, and lateral buds protected by a single 

 external bud-scale 13, in SALICACEAE, p. 20. 



132b. Plums and cherries; with leaves lanceolate or broader, 

 and stipules minute and falling early in the season; lateral 

 buds with more than one bud-scale 30, in ROSACEAE, p. 54. 



133a. With stipules or with stipular scars indicating where stipules 



have been detached 134. 

 133b. Without stipules or stipular scars 138. 



134a. With three bundle-scars in each leaf-scar 135. 

 134b. With one bundle-scar in each leaf-scar 136. 



135a. Willows; usually with slender leaves and twigs and frequently 

 with large conspicuous stipules; lateral buds covered by a 

 single external bud-scale 13, in SALICACEAE, p. 20. 



135b. Juneberries; with oblong or ovate leaves and small stipules 

 which fall early; lateral buds with more than one external 

 scale 42b, in ROSACEAE, p. 55. 



136a. Leaves mostly entire, only a few here and there with low 

 teeth la, in AQUIFOLIACEAE, p. 69. 



136b. Leaves sharply toothed 137. 



137a. Axillary buds superposed, i. e., with a second one just above 



the first Ib, in AQUIFOLIACEAE, p. 69. 



137b. Axillary buds not superposed 2b, in RHAMNACEAE, p. 71. 



138a. Leaves with purple petioles, which are at least one-fourth 

 as long as the blade la, in AQUIFOLIACEAE, p. 69. 



138b. Leaves short-petioled or sessile 139. 



139a. Stems erect and straight, unbranched or with very few branches 



27, in ROSACEAE, p. 53. 



139b. Stems more or less crooked and freely branched, making a 

 spreading shrub 25, in ERICACEAE, p. 86. 



140 



140a. Flowers appearing In autumn, after the leaves have fallen 



HAMAMELIDACEAE, p. 51. 



140b. Flowers appearing in spring, before the leaves have 

 opened 141. 



